Oxford researchers have confirmed the presence of honey in a 2,500-year-old shrine near Pompeii, resolving a decades-long debate about the contents of ancient bronze jars found at the site. The shrine, first discovered in 1954, contained several jars with an orange-brown sticky residue. Earlier analyses over the past thirty years failed to verify that the substance was honey, instead suggesting it was animal or vegetable fat contaminated with pollen and insect parts.
The new study used advanced analytical techniques, including mass spectrometry for proteins and small molecule analysis, to determine the molecular composition of the residue. This approach enabled researchers to identify sugars, organic acids, and royal jelly proteins—components that would not have been detected using previous methods. The findings showed that the chemical fingerprint of the ancient residue closely matched modern beeswax and was similar to modern honey.
Further comparison with modern honeycomb samples and simulations of degraded honeycomb provided additional evidence supporting these results.
Professor James McCullagh, Director of Oxford’s Mass Spectrometry Research Facility in the Department of Chemistry and co-lead on the project, said: “The application of multiple analytical techniques was key to the success of this study. By applying several mass spectrometry and spectroscopic approaches we were able to reveal a comprehensive picture of the residue’s molecular composition — enabling us to distinguish between contaminants, degradation products, and original biomarkers.”
Lead author Dr Luciana da Costa Carvalho explained how X-ray photoelectron spectroscopy revealed copper corrosion products associated with the residue: “Copper ions are naturally biocidal, and we believe their presence may have helped protect the sugar markers in this area from microbial decay.”
The research was made possible through collaboration between Oxford’s Ashmolean Museum and Italian archaeological institutions. Dr Kelly Domoney, Heritage Science Manager at the Ashmolean Museum who also co-led the study, said: “In preparation for the exhibition ‘Last Supper in Pompeii’ at the Ashmolean Museum in 2019, our colleagues at the Archaeological Park of Paestum and Veila generously made several important and high-profile loans, including a Greek bronze hydria from the Heroon and its organic contents. We were permitted a unique opportunity to re-analyse those contents using modern instrumentation at the University.”
For this exhibition, 37 objects underwent detailed assessment using microscopy and X-radiography. These examinations revealed new details about how some vessels were used—for example, soot residues indicated use over cooking hearths while limescale buildup suggested others served as kettles for heating water.
Co-author Elisabete Pires highlighted a major development in their research: “The turning point in the project came with the identification of major royal jelly proteins all specific to honeybee secretions. Our results demonstrate the power of bottom-up proteomics combined with metabolomics in the investigation of archaeological samples.”
Dr Gabriel Zuchtriegel, Director of Archaeological Park of Pompeii and former Director at Paestum & Velia added: “The application of chemical and scientific analyses to extract new and detailed information from existing artefacts allows us to adopt a more informed and nuanced approach to understanding the lives and rituals of past societies, and all from material that already lines the shelves of every archaeological museum collection.”
Researchers hope these findings will encourage further analysis of legacy materials held by museums worldwide—especially where earlier tests proved inconclusive or sampling is limited.
The full study has been published in The Journal of the American Chemical Society.